Wheeled vehicle mounted with RFID tag, RFID tag, speed measurement system, and speed measurement method

ABSTRACT

An RFID tag having a memory portion for holding information on a wheeled vehicle is mounted on the wheeled vehicle, and an external interrogator and the RFID tag exchange information with each other. Further, an RFID tag having a memory portion for holding information on a wheeled vehicle and a communication device for exchanging information with the RFID tag are set on the wheeled vehicle. When the external interrogator and the RFID tag exchange information with each other, the communication device holds information of a situation, for example, speed information, information on date and time, and the like in the memory portion in the RFID tag.

TECHNICAL FIELD

The present invention relates to a wheeled vehicle mounted with an RFIDtag, an RFID tag, a speed measurement system, and a speed measurementmethod.

BACKGROUND ART

Conventionally, speed monitoring of wheeled vehicles, using automaticspeed check equipment, is performed. Automatic speed check equipment isplaced at capital highways, roadsides where speeding occurs frequentlyor the like, the speed of wheeled vehicles, which are driven withexceeding the legal speed (speed limit), is measured, and the carregistration plates and drivers of the wheeled vehicles arephotographed. If speeding is detected by the automatic speed checkequipment, a notification is sent to a possessor of the wheeled vehicleat a later date based on the photograph.

However, the automatic speed check equipment is extremely large-scaledequipment, and there is a problem that the automatic speed checkequipment cannot be placed other than at a specific region. In addition,in the case of using the conventional automatic speed check equipment,it is necessary to post a sign indicating placement of the automaticspeed check equipment in the advance due to issues such as the rights ofportrait, because the driver and the like are photographed. Therefore,it is possible for drivers to drive the wheeled vehicles with speed thatis dropped to the legal speed or less only in the specific region wherethe automatic speed check equipment is placed, and to drive the wheeledvehicles with speed that exceeds the legal speed in other regions.

Moreover, there is a problem of malfunction in the automatic speed checkequipment. In the automatic speed check equipment that operatesautomatically as its name suggests, regular and detailed maintenance isrequired for the properties thereof and the purpose of placement.However, since the automatic speed check equipment is large-scaledequipment, the burden of maintenance becomes large, and the detailedmaintenance is difficult. Therefore, there are a quite a few cases thatthe automatic speed check equipment operates even if the wheeledvehicles drive within the legal speed. Furthermore, in such a case, itis difficult to prove the malfunction.

In recent years, a large number of new monitoring systems of speed andthe like have been proposed; however, such systems also have manyproblems. For example, a system for monitoring and measuring speed usingETC (Electronic Toll Collection: automatic toll collection system) isproposed in References 1 and 2 (Japanese Published Patent ApplicationNo. 2003-346283 and Japanese Published Patent Application No.2006-107315). The system is to obtain information on wheeled vehiclesand personal information with the use of an IC card for ETC, utilizing agate for ETC placed at toll roads and highways and a car-mount devicefor ETC. Even in such a system, a problem of the equipment being largescale is not solved, and whether or not the car-mount device is setdepends on an individual. Moreover, there is a problem that it is easyto turn on/off the car-mount device. That is, there is difficulty inusing the above system to “crackdown on speeding” that is very public,in terms of fairness.

A system for warning an alert on the car-mount device of the speedingwheeled vehicles using a car-mount device for VICS (vehicle informationand communication system) and an optical beacon (+an ID detector) isproposed in Reference 3 (Japanese Published Patent Application No.H11-312282). In the system, there are also problems that the device islarge scale, turning on/off the car-mount device is easy, and whether ornot the car-mount device is set depends on the individual. Furthermore,there is a problem that the vehicle ID is not fixed. Therefore, such asystem is unsuitable for using crackdown on speeding and the like.

In each proposal of References 1 to 3, a solution to the problem ofmalfunction that has exited conventionally is not proposed. Ifmalfunction occurs, a method for verifying malfunction does not exit.

DISCLOSURE OF INVENTION

In accordance with the above-described, crackdown using automatic speedcheck equipment of which placement regions are defined becomes justnominal crackdown and does not suppress driving with excessive legalspeed. Although it may be considered that the above problems are solvedby increasing the placement number of equipment and monitoring all roadssubstantially, it is not practical in view of cost for placement.Furthermore, for the purpose of crackdown on speeding, the problem ofmalfunction is serious.

In view of the above problems, it is an object of the present inventionto provide a wheeled vehicle or the like that is effective for obtainingspeed information and the like.

Further, it is an object of the present invention to provide a speedmeasurement system of which degree of freedom of a placement region isexpanded, a speed measurement method, and the like. It is another objectto provide a speed measurement system that can reduce malfunction, ofwhich maintenance is easy, a speed measurement method, and the like.Furthermore, it is still another object to provide a speed measurementsystem that is capable of verifying whether or not malfunction hasoccurred in a case where malfunction occurs, and the like.

The present invention is to efficiently perform, for example, crackdownon speeding by mounting an RFID tag having a memory portion for holdinginformation on a wheeled vehicle on the wheeled vehicle, and performingcommunication between an external interrogator and the RFID tag. Theinterrogator may be able to read the information stored in the RFID tag.The interrogator may be able to write the information to the storage ofthe RFID tag.

In the present invention, in a case where an RFID tag having a memoryportion for holding information on a wheeled vehicle and a communicationdevice that communicates with the RFID tag are set on the wheeledvehicle, and where an external interrogator and the RFID tag communicatewith each other, the communication device holds information of asituation, for example, speed information, time and date, and the likein the memory portion in the RFID tag. Accordingly, if the systemmalfunctions, whether or not malfunction occurs can be verified.

Further, in the present invention, an RFID tag having a memory portionfor holding information on a wheeled vehicle, a battery that can becharged, and a charge control circuit is used. Accordingly, the RFID tagcan operate by power from the battery, and a response speed can beimproved. A probability of malfunction can be reduced.

It is to be noted that a reader/writer that can be used in the presentinvention is small compared with a conventional speed detection device,and it can be carried around.

One aspect of the present invention is a wheeled vehicle including anRFID tag provided with a memory portion for holding information on awheeled vehicle, where the memory portion holds identificationinformation on a wheeled vehicle, and the RFID tag sends identificationinformation on a wheeled vehicle to a interrogator in a case ofreceiving a signal from the interrogator.

Another aspect of the present invention is a wheeled vehicle includingan RFID tag provided with a memory portion for holding information on awheeled vehicle and a communication device for communicating with theRFID tag, where the memory portion holds identification information on awheeled vehicle, the RFID tag sends identification information on awheeled vehicle to a interrogator in a case of receiving a signal fromthe interrogator, the communication device sends speed information thatis measured by the wheeled vehicle to the RFID tag in a case wherecommunication is performed between the RFID tag and the interrogator,and the RFID tag holds the speed information that is measured by thewheeled vehicle in the memory portion.

Another aspect of the present invention is a wheeled vehicle includingan RFID tag provided with a memory portion for holding information on awheeled vehicle, a battery that can be charged, and a charge controlcircuit, where the memory portion holds identification information on awheeled vehicle, the charge control circuit examines whether or not avoltage of the battery reaches a given value and charges the battery ina case where the RIFD tag receives a signal from a interrogator, and theRFID tag sends identification information on a wheeled vehicle to theinterrogator.

Another aspect of the present invention is a wheeled vehicle includingan RFID tag provided with a memory portion for holding information on awheeled vehicle, a battery that can be charged, and a charge controlcircuit, and a communication device for communicating with the RFID tag,where the memory portion holds identification information on a wheeledvehicle, the charge control circuit examines whether or not a voltage ofthe battery reaches a given value and charges battery in a case wherethe RFID tag receives a signal from a interrogator, the RFID tag sendsidentification information on a wheeled vehicle to the interrogator, thecommunication device sends speed information that is measured by thewheeled vehicle to the interrogator in a case where communication isperformed between the RFID tag and the interrogator, and the RFID tagholds the speed information that is measured by the wheeled vehicle inthe memory portion.

In the above structure, the RFID tag may be attached to any of a mirrorportion, a light portion, and a window portion of a wheeled vehicle.

One aspect of the present invention is an RFID tag including a memoryportion for holding information on a wheeled vehicle, a battery that canbe charged, and a charge control circuit, where the memory portion holdsinformation on a wheeled vehicle and sends information on a wheeledvehicle to a interrogator in a case of receiving a signal from theinterrogator, and the charge control circuit examines whether or not avoltage of the battery reaches a given value and charges the battery.

Another aspect of the present invention is an RFID tag including amemory portion for holding information on a wheeled vehicle, a batterythat can be charged, and a charge control circuit, where the memoryportion holds information on a wheeled vehicle and sends information ona wheeled vehicle to a interrogator in a case of receiving a signal froma interrogator, and the charge control circuit examines whether or not avoltage of the battery reaches a given value and charges the battery ina case where the voltage of the battery does not reach the given value.

One aspect of the present invention is a speed measurement systemincluding a first interrogator and a second interrogator which detectinformation on an RFID tag set on a wheeled vehicle and are placed tohave a given distance between the first interrogator and the secondinterrogator, and an information processing unit connected to the firstinterrogator and the second interrogator, where after the firstinterrogator detects identification information on a wheeled vehicleheld in a memory portion in the RFID tag, the second interrogatordetects identification information on a wheeled vehicle held in thememory portion in the RFID tag; and the information processing unitincludes a first unit for holding information on date and time indetecting the identification information on a wheeled vehicle by thefirst interrogator, a second unit for holding information on date andtime in detecting the identification information of a wheeled vehicle bythe second interrogator, a unit for calculating a difference of timebetween the first information on date and time and the secondinformation on date and time, and a unit for calculating average speedbased on a difference of time between the first information on date andtime and the second information on date and time and based on a distancebetween the first interrogator and the second interrogator.

In the above structure, the information processing unit may be acomputer. The first interrogator and the second interrogator, and theinformation processing unit may be connected with or without a wire.

Another aspect of the present invention is a speed measurement systemincluding a first interrogator and a second interrogator which detectinformation on an RFID tag set on a wheeled vehicle and are placed tohave a given distance between the first interrogator and the secondinterrogator, and a computer connected to the first interrogator and thesecond interrogator, where after the first interrogator detectsidentification information on a wheeled held in a memory portion in theRFID tag, the second interrogator detects the identification informationon a wheeled vehicle held in the memory portion in the RFID tag; and thecomputer holds a first information on date and time in detecting theidentification information on a wheeled vehicle by the firstinterrogator and a second information on date and time in detecting theidentification information on a wheeled vehicle by the secondinterrogator, and calculates average speed of a wheeled vehicle betweenthe first interrogator and the second interrogator by calculating adifference of time between the first information on date and time andthe second information on date and time.

In the above structure, the computer may be a server computer or acomputer connected to a lower part of the server computer. The wheeledvehicle may have a communication device for communicating with the RFIDtag. Further, the RFID tag may be provided with a battery that can becharged and a charge control circuit. Furthermore, the firstinterrogator and the second interrogator, and the computer may beconnected with or without a wire.

One aspect of the present invention is a method for measuring speedincluding the steps of placing a first interrogator and a secondinterrogator, which detect information on an RFID tag set on a wheeledvehicle, to have a given distance between the first interrogator and thesecond interrogator, measuring date and time of the wheeled vehiclepassing through the first interrogator by detecting identificationinformation on a wheeled vehicle held in a memory portion in the RFIDtag by the first interrogator, measuring date and time of the wheeledvehicle passing though the second interrogator by detectingidentification information on a wheeled vehicle held in the memoryportion in the RFID tag by the second interrogator, determining adifference between date and time of the wheeled vehicle passing throughthe first interrogator and date and time of the wheeled vehicle passingthrough the second interrogator, and calculating average speed of thewheeled vehicle based on the difference of date and time and thedistance between the first interrogator and the second interrogator.

In the above structure, when the first interrogator or the secondinterrogator detect the identification information on a wheeled vehicle,the memory portion in the RFID tag may hold speed information that isindividually measured by the wheeled vehicle. Further, when the firstinterrogator or the second interrogator detect the identificationinformation on a wheeled vehicle, the battery in the RFID tag may becharged.

It is to be noted that the above information on a wheeled vehicle mayinclude any of identification information on a wheeled vehicle, speedinformation, information on date and time, information on theft,information on accident history, information on restoration history,information on tax payment, and information on penalty payment.

The above information on a wheeled vehicle is not particularly limitedas long as it is information on a wheeled vehicle. The aboveidentification information on a wheeled vehicle (vehicle ID) may be avehicle number, a license number, or another identification information.

In addition to a method in which two interrogators are used as describedabove, a method for calculating speed using one interrogator isconsidered. As a method for calculating speed using one interrogator,for example, a method using a communication distance that is keptconstant between a interrogator and an RFID tag is given. In the method,time at which detection of identification information on a wheeledvehicle starts and time at which detection of identification informationon a wheeled vehicle is completed are measured, whereby time needed forthe wheeled vehicle passing through the communication distance iscalculated. Accordingly, a simpler speed detection system can beconstructed.

By using the wheeled vehicle and the speed measurement system of thepresent invention, crackdown on speeding becomes easy.

If malfunction of the system occurs, whether or not malfunction hasoccurred can be easily verified.

A interrogator for exchanging information with an RFID tag set on awheeled vehicle is a small device, and it can be carried, for example,when police officers go on patrol. Thus, it produces a large effect onfinding stolen vehicles, revelation of illegal parking, or the like.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A to 1C are views illustrating a method for measuring speed ofthe present invention.

FIG. 2 is a flow chart showing a flow of calculating speed of thepresent invention.

FIGS. 3A to 3C are views each illustrating an example of setting an RFIDtag on a wheeled vehicle of the present invention.

FIGS. 4A to 4D are views each illustrating an example of placing ainterrogator of the present invention.

FIGS. 5A to 5E are views each illustrating an example of placing ainterrogator of the present invention.

FIGS. 6A to 6E are views illustrating a process for manufacturing anRFID tag of the present invention.

FIGS. 7A to 7D are views illustrating a process for manufacturing anRFID tag of the present invention.

FIGS. 8A and 8B are views illustrating a process and the like formanufacturing an RFID tag of the present invention.

FIGS. 9A and 9B are views each illustrating a method for measuring speedof the present invention.

FIG. 10 is a flow chart showing a flow of calculating speed of thepresent invention.

FIGS. 11A to 11C are views each illustrating a method for tracking astolen vehicle of the present invention.

FIG. 12 is a flow chart showing a flow of tracking a stolen vehicle ofthe present invention.

FIGS. 13A and 13B are views each showing a placement example of ainterrogator of the present invention.

FIGS. 14A to 14C are views each illustrating a structure of an RFID tagand a interrogator of the present invention.

FIGS. 15A and 15B are views showing a flow and the like of charging anRFID tag of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiment modes of the present invention will be describedin detail with reference to the accompanying drawings. However, thepresent invention is not limited to the following description, and it iseasily understood by those skilled in the art that various changes andmodifications are possible, unless such changes and modifications departfrom the content and the scope of the invention. Therefore, the presentinvention is not construed as being limited to the description of thefollowing embodiment modes. It is to be noted that like portions in thedrawings may be denoted by the like reference numerals in a structure ofthe present invention to be given below.

In addition, the present invention can be applied to a semiconductordevice which uses any of frequency modes, for example, a long wave band(135 kHz or the like), a short wave band (6.78 MHz, 13.56 MHz, 27.125MHz, 40.68 MHz, or the like), an ultra-short wave band (433.92 MHz,869.0 MHz, 915.0 MHz, or the like), a microwave band (2.45 GHz, 5.8 GHz,24.125 GHz, or the like), or the like without being limited to aspecific frequency mode to be used. A frequency mode may be selected asappropriate depending on request of a communication distance,directivity, or the like. Although a semiconductor device that sends andreceives data used in the present invention is called an RFID (RadioFrequency IDentification) tag, an RF tag, an RF chip, a wireless tag, awireless processor, a wireless memory, an IC (Integrated Circuit) tag,an IC label, an electronic tag, an electronic chip, or the like, thesemiconductor device is uniformly referred to as an “RFID tag” in thepresent specification.

Embodiment Mode 1

In this embodiment mode, a wheeled vehicle mounted with an RFID tag andbrief description of a speed measurement system using the wheeledvehicle will be described with reference to FIGS. 1A to 6E.

FIGS. 1A to 1C show a typical example of a method for measuring speed.In FIGS. 1A to 1C, an RFID tag 102 is mounted on a wheeled vehicle 104,which has a memory portion that holds unique vehicle identificationinformation on a wheeled vehicle (hereinafter, referred to as vehicleID). The wheeled vehicle 104 approaches a first interrogator 106 placedon a road 100 or passes through the interrogator 106 (see FIG. 1A). Atthis time, the first interrogator 106 sends vehicle ID that is obtainedby communication with an RFID tag to a server computer 110 that isnetwork-connected. The server computer 110 holds the vehicle ID andinformation on date and time of the vehicle ID obtained by the firstinterrogator 106, simultaneously.

Next, the wheeled vehicle 104 approaches a second interrogator 108 orpasses through the second reader/wrier 108 (see FIG. 1B). At this time,the server computer 110 holds vehicle ID and information on date andtime of the vehicle ID obtained by the second interrogator 108,simultaneously, with the similar procedure in a case where the wheeledvehicle 104 passes through the first interrogator 106.

After that, the server computer 110 extracts a pair of date and timewith the same vehicle IDs and calculates a difference thereof. In otherwords, the sever computer 110 calculates the time period that is neededfor the wheeled vehicle 104 driven from a point A where the firstinterrogator 106 is placed to a point B where the second interrogator108 is placed.

A distance between the point A and the point B is measured in advanceand the distance is divided by the time period that is calculated by theabove method, whereby average speed between the point A and the point Bcan be determined.

In a case where the average speed exceeds legal speed, the servercomputer holds data of date and time, a place (including unique IDassigned to the interrogator or the like), speed, excess speed, and thelike. At a later date, in accordance with the data, a notification ofspeeding can be sent to a possessor of the wheeled vehicle.

Information that is held in the RFID tag is not limited to informationon date and time and speed information. For example, the RFID tag mayhold information on a place of excess speed or the like in addition tothe above information. Further, in terms of making management of aplurality of interrogators by the server computer easy, eachinterrogator preferably has unique ID.

Details of operation of a server computer that can be used in thisembodiment mode are shown in FIG. 1C. In this embodiment mode, theserver computer is uniformly used; however, it is not particularlylimited as long as it is an information processing unit. For example, acomputer connected to a lower part of the server computer, or anotherstructure may be used. Furthermore, details of the sever computer shownin FIG. 1C is just one example, and it is not limited to this.

A signal including vehicle ID that is sent from the first interrogator106 is inputted to a signal processing unit 120 of the server computer110. The signal inputted to the signal processing unit 120 is convertedto data suitable for arithmetic processing, and then the signal isinputted to a storage unit 124 through an arithmetic unit 122 and held.At this time, information on date and time is stored simultaneously withvehicle ID. The information on date and time may be measured by thefirst interrogator 106 or may be information at the time where thevehicle ID is inputted to the storage unit 124 of the server computer.Subsequently, a signal including vehicle ID that is sent from the secondinterrogator 108 is inputted to the storage unit 124 and held throughthe similar process as with the case of the first interrogator 106.

Then, the arithmetic unit 122 extracts a pair of information on date andtime with the same vehicle IDs, and a difference thereof is calculated.In other words, time period that is needed for the wheeled vehicle 104driven from the point A where the first interrogator 106 is placed tothe point B where the second interrogator 108 is placed is calculated.After that, average speed is determined with the use of the distancebetween the point A and the point B that is held in the storage unit 124in advance. In a case where the average speed exceeds legal speed of aregion including the point A and the point B, the excess average speedand vehicle ID are inputted together to the storage unit 124 and held.Then, excess of legal speed is notified as appropriate with the use ofan external output unit 126 or the like.

FIG. 2 shows a flow chart for calculating speed of the wheeled vehicledescribed in the above.

As a step S210, the first interrogator detects vehicle ID of the wheeledvehicle that approaches or passes through the first interrogator. As astep S220, the vehicle ID and information on date and time are stored onthe sever computer.

As a step S230, the second interrogator detects vehicle ID of a wheeledvehicle that approaches or passes through the second interrogator. As astep S240, the vehicle ID and information on date and time are stored onthe server computer.

After the step S240, as a step S250, the server computer extracts a pairof information on date and time with the same vehicle IDs. It is to benoted that the step S250 may be conducted simultaneously with the stepS240. In this case, information on vehicle ID that corresponds to thevehicle ID detected by the step S230 (information stored by the stepS220) is extracted, and speed is calculated in the subsequent step.

Next, as a step S260, the sever computer calculates time period that isneeded for the driving between the first interrogator and the secondinterrogator from the extracted information on date and time, andcalculates average speed with the use of the distance between the firstinterrogator and the second interrogator.

In the subsequent step S270, the calculated average speed and legalspeed are compared, and it is examined that whether the calculatedaverage speed is speeding or not. When the average speed is determinedas the speeding here (in a case of YES in FIG. 2), as a step S280,information on speeding such as date and time, a place (including uniqueID assigned to the interrogator or the like), speed, and excess of speedare stored on the sever computer. To the contrary, when the averagespeed is not speeding, the flow is completed without storing informationon speeding.

In the present invention, whether the above process is conducted by asoftware or hardware is not particularly limited.

In FIGS. 3A to 3C, examples of setting an RFID tag on wheeled vehiclesare shown.

FIG. 3A shows an example of setting an RFID tag 300 of the presentinvention on a side mirror 302 of a wheeled vehicle. When the RFID tag300 is set to be in contact with a portion having conductivity such asmetal, defects may be generated in communication. Therefore, it ispreferable to avoid the RFID tag 300 to be set at a portion havingconductivity. The side mirror 302 shown in FIG. 3A is formed from aresin material in many cases, and it is favorable for a setting portionof the RFID tag 300.

Although FIG. 3A shows a structure where the RFID tag 300 is attached toa surface of the side mirror 302, the RFID tag 300 may be embedded inthe side mirror 302. Alternatively, the RFID tag 300 may be attached toa mirror part included in the side mirror 302 or may be embedded in themirror part thereof.

FIG. 3B shows an example of setting the RFID tag 300 of the presentinvention on a headlight 304 of a wheeled vehicle. The headlight 304 isformed from glass, a resin, or the like in many case, and it isfavorable for a setting portion of the RFID tag 300.

Although FIG. 3B shows a structure where the RFID tag 300 is attached toa surface of the headlight 304, the RFID tag 300 may be embedded in theheadlight 304. Alternatively, the RFID tag 300 may be set in a spaceinside of the headlight 304.

Naturally, the setting portion of the RFID tag of the present inventionis not limited to the headlight. The RFID tag may be attached to ablinker or another light or may be embedded therein.

FIG. 3C shows an example of setting the RFID tag 300 of the presentinvention on a windshield 306 of a wheeled vehicle. The windshield 306is formed from glass or the like, and it is favorable for a settingportion of the RFID tag 300.

Although FIG. 3C shows a structure where the RFID tag 300 is attached toa surface of the windshield 306, the RFID tag 300 may be embedded in thewindshield 306. Alternatively, the setting place of the presentinvention is not limited to the windshield, and the RFID tag 300 may beattached to a rear windshield or another window or may be embeddedtherein.

It is to be noted that FIGS. 3A to 3C are just one example, and the RFIDtag may be in any position as long as the function of the presentinvention can be secured. For example, the RFID tag may be attached to aportion that is formed from a resin material inside the wheeled vehicleor may be embedded therein. In a case where a serious problem is notcaused even when the RFID tag 300 is set at a portion havingconductivity, the RFID tag 300 may be set at a portion havingconductivity. Further, it is not limited to one RFID tag that is set onone wheeled vehicle, and two or more RFID tags may be set on one wheeledvehicle. By providing a plurality of RFID tags, redundancy to breakdownof the RFID tag or the like can be generated.

FIGS. 4A to 4D show examples of setting a interrogator of the presentinvention. FIG. 4A to 4D are views for showing placement of ainterrogator; therefore, an RFID tag set on a wheeled vehicle is notshown.

FIG. 4A shows an example in which a interrogator 402 and a interrogator404 are placed on a road 400 and speed of a wheeled vehicle 406 ismeasured. As the placement example of the interrogator shown in FIG. 4A,for example, simplified speed check equipment can be given. Since theinterrogator is relatively small in size and is easily carried, it canbe placed in a short time period. Therefore, in a case where crackdownis temporarily strengthened, it is extremely effective to use thesetting example as shown in FIG. 4A. In FIG. 4A, an example in which atripod is used as a placement method of the interrogator; however, it isnot limited thereto. The interrogator may be directly placed on a road.

FIG. 4B shows an example in which the interrogator 402 and theinterrogator 404 are placed in the ground of the road 400 and speed ofthe wheeled vehicle 406 is measured. The example of FIG. 4B can use forexample, fixed-type speed check equipment. In a case of using theplacement example shown in FIG. 4B, an RFID tag is preferably set in thevicinity of a lower part (bottom) of the wheeled vehicle 406. However,the setting position of the RFID tag is not limited to the vicinity of alower part (bottom) as long as a problem is not caused in measuringspeed.

FIG. 4C shows an example in which the interrogator 402 and theinterrogator 404 are set on a telephone pole (in FIG. 4C, a telephonepole 408 and a telephone pole 410) or the like placed at the side of theroad 400, and speed of the wheeled vehicle 406 is measured. The exampleof FIG. 4C can use for example, fixed-type speed check equipment. In acase of using the setting example shown in FIG. 4C, an RFID tag ispreferably set on a side portion or in the vicinity of a top portion ofthe wheeled vehicle 406. However, the setting position of the RFID tagis not limited to a side portion or the vicinity of a top position aslong as a problem is not caused in measuring speed.

FIG. 4D shows an example in which the interrogator 402 and theinterrogator 404 are placed in a tunnel 412, and speed of the wheeledvehicle 406 driven on the road 400 is measured. The example of FIG. 4Dcan use for example, fixed-type speed check equipment. In a case ofusing the placement example shown in FIG. 4D, an RFID tag is preferablyset in the vicinity of a top portion of the wheeled vehicle 406.However, the setting position of the RFID tag is not limited to thevicinity of a top position as long as a problem is not caused inmeasuring speed.

In FIGS. 5A to 5E, the placement examples of the interrogator are shownas plan views. It is to be noted that the RFID tag mounted on thewheeled vehicle is not illustrated for simplicity.

FIG. 5A shows an example in which a interrogator 504, a interrogator506, a interrogator 508, and a interrogator 510 are placed in order tomeasure speed of a wheeled vehicle 502 driven on a road 500. As theplacement example shown in FIG. 5A, for example, simplified speed checkequipment can be given. Since the interrogator is relatively small insize and is easily carried, it can be set in a short time period.Therefore, in a case where crackdown is temporarily strengthened, it isextremely effective to use the placement example shown in FIG. 5A.Naturally, the placement of FIG. 5A can be used for fixed-type speedcheck equipment.

In FIG. 5A, the interrogators are placed on each of a lane where thewheeled vehicle 502 is driven and an opposite lane. By such a structure,speed can be measured with high accuracy regardless of the lane wherethe wheeled vehicle is driven. The number of interrogators may beincreased or decreased as appropriate depending on the number of lanes,width of a road, and the like. In a case of measuring speed of thewheeled vehicle 502 of FIG. 5A, the interrogator 506 functions as afirst interrogator, and the interrogator 510 functions as a secondinterrogator because the traveling direction of the wheeled vehicle 502is in the right direction in the drawing. However, it is not limitedthereto.

FIG. 5B shows an example in which the interrogator 504, the interrogator506, the interrogator 508, and the interrogator 510 are placed in theground of the road 500. The example of FIG. 5B can use fixed-type speedcheck equipment. In FIG. 5B, the interrogators are each placed on a lanewhere the wheeled vehicle 502 is driven and an opposite lane, as similarto FIG. 5A. By such a structure, speed can be measured with highaccuracy regardless of the lane where the wheeled vehicle is driven. Thenumber of interrogators may be increased or decreased as appropriatedepending on the number of lanes, width of the road, and the like.

In a case of using the placement example shown in FIG. 5B, an RFID tagis preferably set in the vicinity of a lower part (bottom) of thewheeled vehicle 502. However, in a case of a setting position whereproblems are not caused in measuring speed, the position of the RFID tagis not limited to the vicinity of the lower part (bottom).

FIG. 5C shows an example in which the interrogator 504 and theinterrogator 508 are placed in the ground of the center part of the road500. By such a structure, speed can be measured with high accuracyregardless of the lane where the wheeled vehicle is driven while theplacement number of interrogators is suppressed. However, in a casewhere the width of the road 500 drastically exceeds a communicationdistance, the structure shown in FIG. 5B is preferably used. The exampleof FIG. 5C can use for example, fixed-type speed check equipment. In acase of using the placement example shown in FIG. 5C, an RFID tag ispreferably set in the vicinity of a lower part (bottom) of the wheeledvehicle 502. However, in a case of a setting position where problems arenot caused in measuring speed, the position of the RFID tag is notlimited to the vicinity of the lower part (bottom).

FIG. 5D shows an example in which a interrogator 512 and a interrogator514 are added to the structure of FIG. 5A. By such a structure, averagespeed of three sections can be determined. The three sections are asection between the interrogator 504 (506) and the interrogator 512(514), a section between the interrogator 504 (506) and the interrogator508 (510), and a section between the interrogator 512 (514) and theinterrogator 508 (510).

By such a structure, transition of the average speed can be examined,and for example, dangerous driving such as rapid acceleration ordeceleration can be detected. In addition to the structure of FIG. 5D,by placing a large number of interrogators, approximate instantaneousspeed can be measured. Further, the instantaneous speed is measured at aplurality of points, whereby acceleration can be determined.

FIG. 5E shows an example in which interrogators are placed on the roadof one lane. In FIG. 5E, the interrogator 504 and the interrogator 508are placed in the ground of the central portion of the road 500, assimilar to FIG. 5C. On a road of one lane as shown in FIG. 5E, thetraveling direction of wheeled vehicles is not constant. Accordingly,either interrogator corresponds to the first interrogator or the secondreader/wrier is determined depending on the traveling direction of thewheeled vehicles. For example, in a case where the wheeled vehicletravels in the left direction in the drawing, the interrogator 504functions as the first interrogator and the interrogator 508 functionsas the second interrogator. Alternatively, the wheeled vehicle travelsin the right direction in the drawing, the interrogator 508 functions asthe first interrogator and the interrogator 504 functions as the secondinterrogator.

Information on date and time that is held in the server computer whenthe wheeled vehicle passes through the interrogator determines whichinterrogator corresponds to the first interrogator or the secondinterrogator. In other words, by comparing each information on date andtime of a pair of the interrogator 504 and the interrogator 508, theinterrogator which holds information on earlier time is the firstinterrogator, and the interrogator which holds information on later timeis the second interrogator.

As described above, the concept of the first interrogator and the secondinterrogator is one of convenience. In actual calculating speed, speedcan be calculated by comparing information on date and time with thesame vehicle IDs without specifically determining the first interrogatorand the second interrogator.

By such a structure, speed can be measured with high accuracy even on aroad of one lane. The setting example of FIG. 5E can use for example,fixed-type speed check equipment. In a case of using the placementexample shown in FIG. 5E, an RFID tag is preferably set in the vicinityof a lower part (bottom) of the wheeled vehicle 502. However, in a caseof a setting position where problems are not caused in measuring speed,the position of the RFID tag is not limited to the vicinity of the lowerpart (bottom). Further, on a road of one lane, the structure such asFIG. 5A or FIG. 5D can be used.

The placement examples of FIGS. 4A to 4D and FIGS. 5A to 5E are just oneexample, and any placement may be employed as long as the function ofthe present invention can be secured.

Manufacturing steps of an RFID tag that can be used in the presentinvention are described with reference to FIGS. 6A to 8B. Although, inthis embodiment mode, an example of forming an RFID tag over the glasssubstrate is shown, it is not limited thereto. An RFID tag may be formedusing a silicon substrate.

First, a peeling layer 602 is formed over a surface of a substrate 600(see FIG. 6A). As the substrate 600, one in which an insulating layer isformed over a surface of a glass substrate, a quartz substrate, a metalsubstrate, or a stainless substrate, a plastic substrate having heatresistance capable of resisting processing temperature of these steps,or the like can be used. Since the substrate 600 as the above has nolimitation on the size and shape, for example, it is possible to use arectangular substrate of which one side is one meter or more. By usingsuch a large-sized rectangular substrate, productivity can bedrastically improved. This is the large advantage in comparison with thecase of manufacturing an RFID tag from a circular silicon substrate.

A thin film integrated circuit formed over the substrate 600 is peeledfrom the substrate 600 in the subsequent steps. That is, the RFID tagmanufactured in this embodiment mode does not include the substrate 600.Accordingly, the substrate 600 from which the thin film integratedcircuit is peeled can be reused. In this manner, when the substrate 600is reused, even if an expensive quartz substrate is used, cost can bereduced, which is preferable.

In this embodiment mode, after a thin film is formed over the surface ofthe substrate 600, the shape thereof is processed using aphotolithography method, so that the peeling layer 602 is selectivelyformed.

The peeling layer 602 is formed to have a single layer or a stackedlayer, which is formed from an element selected from tungsten (W),molybdenum (Mo), titanium (Ti), tantalum (Ta), niobium (Nb), nickel(Ni), cobalt (Co), zirconium (Zr), zinc (Zn), ruthenium (Ru), rhodium(Rh), lead (Pb), osmium (Os), iridium (Ir), or silicon (Si), or an alloymaterial or a compound material containing the element as its maincomponent. A layer containing silicon may be amorphous, microcrystal, orpolycrystal.

When the peeling layer 602 has a single layer structure, it ispreferable to form a tungsten layer, a molybdenum layer, or a layercontaining a mixture of tungsten or molybdenum. Alternatively, it ispreferable to form a layer containing an oxide or oxynitride oftungsten, a layer containing an oxide or oxynitride of molybdenum, or alayer containing an oxide or oxynitride of a mixture of tungsten andmolybdenum. The mixture of tungsten and molybdenum corresponds to analloy of tungsten and molybdenum, for example. In addition, the oxide oftungsten is also referred to as tungsten oxide.

When the peeling layer 602 is a stacked layer structure, a tungstenlayer, a molybdenum layer or a layer containing a mixture of tungstenand molybdenum is preferably formed as a first layer of the peelinglayer 602. Then, as a second layer, an oxide, nitride, oxynitride, ornitride oxide of tungsten, molybdenum or a mixture of tungsten andmolybdenum is preferably formed.

When a stacked layer structure of a layer containing tungsten and alayer containing oxide of tungsten is formed as the peeling layer 602,the following method may be employed: the layer containing tungsten isformed and then a layer containing silicon oxide is formed thereover sothat the layer containing the oxide of tungsten is formed at aninterface between the tungsten layer and the layer containing siliconoxide. This method can be applied to the cases of forming layerscontaining nitride, oxynitride, and nitride oxide of tungsten, and afterforming the layer containing tungsten, a silicon nitride layer, asilicon oxynitride layer, or a silicon nitride oxide layer is formedthereover. It is to be noted that a silicon oxide layer, a siliconoxynitride layer, a silicon nitride oxide layer, or the like formed overthe layer containing tungsten later functions as an insulating layer tobecome a base later.

In forming the oxide of tungsten, the composition thereof is notparticularly limited, and it may be determined based on etching rate orthe like. The composition having the most favorable etching rate is alayer containing oxide of tungsten formed by a sputtering method underthe oxide atmosphere. Accordingly, in order to shorten the manufacturingtime, a layer containing oxide of tungsten is preferably formed as thepeeling layer by a sputtering method under the oxide atmosphere.

Although, in the above step, the peeling layer 602 is formed to be incontact with the substrate 600, it is not limited to this step. Theinsulating layer to be a base may be formed to be in contact with thesubstrate 600, and the peeling layer 602 may be formed to be in contactwith the insulating layer.

Next, an insulating film 604 to be a base is formed to cover the peelinglayer 602 (see FIG. 6B). As the insulating film 604 to be a base, alayer containing oxide of silicon or nitride of silicon is formed tohave a single layer or a stacked layer by a sputtering method, a plasmaCVD method, or the like. The silicon oxide material is a substancecontaining silicon (Si) and oxygen (O), which corresponds to siliconoxide, silicon oxynitride, silicon nitride oxide, or the like. Thesilicon nitride material is a substance containing silicon and nitrogen(N), which corresponds to silicon nitride, silicon oxynitride, siliconnitride oxide, or the like.

Next, a semiconductor film is formed over the insulating film 604 (notshown in the figure). As the semiconductor film, an amorphoussemiconductor film may be formed. Alternatively, a microcrystalsemiconductor film or a crystalline semiconductor film may be formed.Although a material of the semiconductor film is not limited, silicon orsilicon germanium (SiGe) is preferably used. In this embodiment mode, anamorphous silicon film having a film thickness of about greater than orequal to 25 nm and less than or equal to 100 nm (preferably, greaterthan or equal to 30 nm and less than or equal to 60 nm) is formed. Afterthe semiconductor film is formed, a step for removing hydrogen containedin the semiconductor film may be performed. Specifically, thesemiconductor film may be heated at 500° C. for one hour.

Subsequently, an element for promoting crystallization is added to thesemiconductor film. In this embodiment mode, a solution containingnickel (Ni) of greater than or equal to 10 ppm and less than or equal to100 ppm in weight conversion, for example, a nickel acetate solution isapplied to a surface of the semiconductor film using a spin coatingmethod. A method for adding an element for promoting crystallization isnot limited to the above, and addition may be performed using asputtering method, an evaporation method, plasma treatment, or the like.

Then, heat treatment is performed at higher than or equal to 500° C. andlower than or equal to 650° C. for greater than or equal to 4 hours andless than or equal to 24 hours, for example, at 570° C. for 14 hours. Bythis heat treatment, a semiconductor film in which crystallization ispromoted is formed.

As heating treatment, RTA (Rapid Thermal Anneal) using radiation of alamp as a heat source or RTA using heated gas (gas RTA) can be cited.Alternatively, heating treatment using an annealing furnace, heatingtreatment by irradiation with a laser beam, or combination thereof maybe performed.

In a case of irradiation with a laser beam, continuous-wave (CW) laserbeam or a pulsed wave laser beam (pulsed laser beam) can be used. Here,a beam emitted from a gas laser such as an Ar laser, a Kr laser, or anexcimer laser; a laser using, as a medium, single crystalline YAG, YVO₄,forsterite (Mg₂SiO₄), YAlO₃, or GdVO₄ or polycrystalline (ceramic) YAG,Y₂O₃, YVO₄, YAlO₃, or GdVO₄ doped with one or more of Nd, Yb, Cr, Ti,Ho, Er, Tm, and Ta as a dopant; a glass laser; a ruby laser; analexandrite laser; a Ti: sapphire laser; a copper vapor laser; or a goldvapor laser, can be used as the laser beam. By irradiation with a laserbeam having a fundamental wave of such lasers or one of the second tofourth harmonics of these fundamental waves, a crystal with a largegrain size can be obtained. For example, the second harmonic (532 nm) orthe third harmonic (355 nm) of an Nd:YVO₄ laser (fundamental wave of1064 nm) can be used. This laser can be emitted by either CW or pulsedoscillation.

It is to be noted that each laser using, as a medium, single crystallineYAG, YVO₄, forsterite (Mg₂SiO₄), YAlO₃, or GdVO₄ or polycrystalline(ceramic) YAG, Y₂O₃, YVO₄, YAlO₃, or GdVO₄ doped with one or more of Nd,Yb, Cr, Ti, Ho, Er, Tm, and Ta as a dopant; an Ar ion laser; and a Ti:sapphire laser, is capable of continuous oscillation. Further, pulseoscillation thereof can be performed at a repetition rate of 10 MHz ormore by carrying out Q switch operation or mode synchronization. When alaser beam is emitted at a repetition rate of 10 MHz or more, asemiconductor film is irradiated with a next pulse while thesemiconductor film is melted by the laser beam and then solidified.Therefore, unlike the case of using a pulsed laser with a low repetitionrate, a solid-liquid interface can be continuously moved in thesemiconductor film so that crystal grains, which continuously grow in ascanning direction, can be obtained.

In this embodiment mode, nickel (Ni) is used as the element forpromoting crystallization of a semiconductor film. Instead of nickel, anelement such as germanium (Ge), iron (Fe), palladium (Pd), tin (Sn),lead (Pb), cobalt (Co), platinum (Pt), copper (Cu), or gold (Au) may beused.

In accordance with the above step, a crystalline semiconductor film isformed. It is to be noted that an element for promoting crystallizationis included in the crystalline semiconductor film. Therefore, after thecrystallization step, gettering of the element is preferably performed.

Next, the crystalline semiconductor film is etched to form anisland-shaped semiconductor film 606 and an island-shaped semiconductorfilm 608. Then, a gate insulating film 610 is formed to cover theisland-shaped semiconductor film 606 and the island-shaped semiconductorfilm 608 (see FIG. 6C).

The gate insulating film 610 may have a single layer structure or astaked layer structure as long as it is an insulating film containing atleast oxygen or nitride. As a formation method, a plasma CVD method or asputtering method can be used. In this embodiment mode, silicon nitrideoxide (SiN_(x)O_(y) (x>y)) and silicon oxynitride (SiO_(x)N_(y) (x>y))are continuously formed to have a total thickness of 115 nm. In a casewhere a TFT having a channel length of 1 m or less (also referred to asa submicron TFT) is formed, the gate insulating film is preferablyformed to have a thickness of 10 to 50 nm.

Next, a conductive film is formed over the gate insulating film 610 andetched to form a gate electrode 612 and a gate electrode 614 (see FIG.6D). As the gate electrode 612 and the gate electrode 614, for example,a conductive film in which W (tungsten) and tantalum nitride arestacked, a conductive film in which Mo (molybdenum), Al (aluminum), Moare stacked in this order, or a conductive film in which Ti (titanium),Al, Ti are stacked in this order can be used. In this embodiment mode, astacked film of W (tungsten) and tantalum nitride is used.Alternatively, an element selected from gold (Au), silver (Ag), copper(Cu), platinum (Pt), aluminum (Al), chromium (Cr), palladium (Pd),indium (In), molybdenum (Mo), nickel (Ni), lead (Pb), iridium (Ir),rhodium (Rh), tungsten (W), cadmium (Cd), zinc (Zn), iron (Fe), titanium(Ti), zirconium (Zr), or barium (Ba), or an alloy material or a compoundmaterial containing the element as its main component can be used as asingle layer or a stacked layer.

As another method, the gate electrode 612 and the gate electrode 614 maybe formed using a droplet discharging method typified or an inkjetmethod by a printing method by which a material can be discharged at apredetermined portion.

An impurity imparting n-type or p-type conductivity is selectively addedto the island-shaped semiconductor film 606 and the island-shapedsemiconductor film 608 using a resist (not shown) as a mask, which isused in forming the gate electrode 612 and the gate electrode 614 (seeFIG. 6D). As a result, a source region, a drain region, a channelformation region, and the like are formed.

Subsequently, an insulating film 616 is formed (see FIG. 6D). Theinsulating film 616 is formed of a silicon nitride film or a siliconnitride oxide film to have a single layer structure or a stacked layerstructure with a thickness of 100 to 200 nm by a plasma CVD method or asputtering method. In a case of combining a silicon nitride oxide filmor a silicon oxynitride film, film formation can be continuouslyperformed by switching gas. In this embodiment mode, a siliconoxynitride film with a thickness of 100 nm is formed by a plasma CVDmethod. By providing the insulating film 616, various impurities such asoxygen and moisture in the air can be prevented from penetration intothe island-shaped semiconductor film 606 and the island-shapedsemiconductor film 608.

Next, an insulating film 618 is formed (see FIG. 6E). Here, an organicresin film such as polyimide, polyamide, BCB (benzocyclobutene),acrylic, or siloxane; an inorganic interlayer insulating film(insulating film containing silicon such as silicon nitride or siliconoxide); a low-k (low dielectric constant) material; or the like, withwhich the insulating film 616 is coated by a SOG (Spin On Glass) methodor a spin coating method can be used. Alternatively, an oxazole resin,for example, photosensitive polybenzoxazole can be used. Thephotosensitive polybenzoxazole has a low dielectric constant (adielectric constant of 2.9 at 1 MHz at a room temperature), high heatresistance (a thermal decomposition temperature of 550° C. with the risein a temperature of 5° C./min, which is measured by thermogravimetricanalyzer (TGA)), and a low water absorption rate (0.3% at a roomtemperature in 24 hours). An oxazole resin which has a lower dielectricconstant as compared to polyimide is suitable as the insulating film618.

Subsequently, the gate insulating film 610, the insulating film 616, andthe insulating film 618 are patterned by a photolithography method toform contact holes that reach a source region and a drain region (seeFIG. 6E).

Then, a conductive film is formed using a conductive material, and thisconductive material is patterned, so that a wiring 620 is formed. Afterthat, an insulating film 622 is formed, and contact holes that reach thewiring 620 are formed (see FIG. 6E).

After the contact holes are formed, an antenna 624 is formed to coverthe contact holes and the insulating film 622. The antenna 624 can beformed by patterning after a conductive film that is to be the antennais formed over the insulating film 622. The antenna may be formed by adroplet discharging method typified by a printing method or an inkjetmethod (see FIG. 6E).

It is to be noted that a structure of a thin film transistor shown inthis embodiment mode is not limited to the above structure. For example,a lightly doped drain (LDD) region may be provided, or a sidewall may beformed on the side surface of each of the gate electrode 612 and thegate electrode 614. Although a thin film transistor having a single gatestructure is formed in this embodiment mode, a multi-gate structure maybe formed. A bottom gate structure may also be formed, and a dual gatestructure in which two gate electrodes are disposed over and below achannel region with a gate insulating film interposed therebetween maybe formed.

The antenna 624 is formed from an element selected from gold (Au),silver (Ag), copper (Cu), platinum (Pt), aluminum (Al), chromium (Cr),palladium (Pd), indium (In), molybdenum (Mo), nickel (Ni), lead (Pb),iridium (Ir), rhodium (Rh), tungsten (W), cadmium (Cd), zinc (Zn), iron(Fe), titanium (Ti), zirconium (Zr), or barium (Ba), or an alloymaterial or a compound material containing the element as its maincomponent. The antenna 624 may have a singe layer structure or a stackedlayer structure. For example, a stacked structure of a barrier layer andan aluminum layer, a stacked layer structure of a barrier layer, analuminum layer, and a barrier layer, or the like can be employed. Thebarrier layer corresponds to titanium, nitride of titanium, molybdenum,nitride of molybdenum or the like. As a shape of the antenna 624,dipole, circle (a loop antenna, for example), flat rectangular solid (apatch antenna, for example), or the like can be cited.

Next, the insulating film 604, the gate insulating film 610, theinsulating film 616, the insulating film 618, and the insulating film622 are etched by a photolithography method so as to expose the peelinglayer 602, so that an opening 626 and an opening 628 are formed (seeFIG. 7A).

After that, an insulating layer 632 is formed (see FIG. 7B) by an SOGmethod, a droplet discharging method, or the like so as to cover a thinfilm integrated circuit 630 (see FIG. 7A). The insulating layer 632 isformed from an organic material, preferably, formed from an epoxy resin.The thin film integrated circuit 630 is small, thin, and lightweight,and it is not adhered to the substrate; therefore, it is easilyscattered after the peeling layer is removed. However, by forming theinsulating layer 632 around the thin film integrated circuit 630, thethin film integrated circuit 630 is weighed, and scattering from thesubstrate 600 can be prevented. Further, the thin film integratedcircuit 630 itself is thin and weak; however, by forming the insulatinglayer 632, uniform intensity can be secured.

Although the insulating layer 632 is formed on a top face and side facesof the thin film integrated circuit 630 in the structure of FIG. 7B, itis not limited to this structure. The insulating layer 632 may be formedonly on the top face of the thin film integrated circuit 630. Althoughthe step for forming the insulating layer 632 is performed after thestep for forming an opening 626 and an opening 628 in this embodimentmode, it is not limited to this order. After the step for forming aninsulating layer 632 over the insulating film 622 and the antenna 624, aplurality of the insulating layers may be etched to form an opening. Inthis structure, the insulating layer 632 is formed only on the top faceof the thin film integrated circuit 630.

Next, the peeling layer 602 is removed by introducing an etchant intothe opening 626 and the opening 628 (see FIG. 7C). As the etchant, a gasor a liquid containing halogen fluoride or an interhalogen compound isused, for example, chlorine trifluoride (ClF₃) is used as a gascontaining halogen fluoride. Thus, the thin film integrated circuit 630is peeled from the substrate 600.

Subsequently, one of surfaces of the thin film integrated circuit 630 isattached to a first base 634, so that the thin film integrated circuit630 is completely peeled from the substrate 600 (see FIG. 7D).

Then, the other surface of the thin film integrated circuit 630 isattached to a second base 636, and the first base 634 and the secondbase 636 are attached to each other, so that the thin film integratedcircuit 630 is sealed with the first base 634 and the second base 636(see FIG. 8A). Thus, an RFID tag in which the thin film integratedcircuit 630 is sealed with the first base 634 and the second base 636 iscompleted.

As the first base 634 and the second base 636, the following can beused: a film to which antistatic treatment is performed (an antistaticfilm); a film of polypropylene, polyester, vinyl, polyvinyl fluoride,vinyl chloride or the like; paper made of a fibrous material; a stackedfilm of a base material film (polyester, polyamide, an inorganicdeposition film, paper or the like) and an adhesive synthetic resin film(an acrylic-based synthetic resin, an epoxy-based synthetic resin or thelike) or the like. As a film to which antistatic treatment is performed,a film with an antistatic material dispersed in a resin, a film with anantistatic material attached thereon, and the like can be given asexamples. The film with an antistatic material attached thereon may be afilm with an antistatic material attached on one of its surfaces, or afilm with an antistatic material attached on each of its surfaces. Asfor the film with an antistatic material attached on one of itssurfaces, the antistatic material may be attached to the inner surfaceof the film or the outer surface of the film. Furthermore, theantistatic material may be attached to the entire surface of the film,or to part of the film. As the antistatic material, a metal such asaluminum, an indium tin oxide (ITO), amphoteric metal salt surfactant,imidazoline type amphoteric surfactant, a resin material containingcrosslinkable copolymer having a carboxyl group and a quaternaryammonium base on its side chain, and the like can be given as examples.By using antistatic films as the first base 634 and the second base 636,static electricity from outside can be prevented from having adverseeffects on the integrated circuit. The stacked film can be attached tothe treatment object by thermo compression bonding.

An adhesive layer may be provided over each surface of the first base634 and the second base 636, or not. Here, the adhesive layercorresponds to a layer formed from a material containing adhesive suchas heat-curable resin, ultraviolet curable resin, epoxy resin basedadhesive, or resin additive.

Next, an RFID tag capable of sending and receiving data without a wirewill be described.

An RFID tag 800 has function for communicating data without a wire,which includes a power supply circuit 802, a clock generation circuit804, a data demodulation circuit 806, a data modulation circuit 808, acontrol circuit 810 for controlling other circuits, a storage circuit812, and an antenna 814 (see FIG. 8B). It is to be noted that thestorage circuit is not necessary to be one circuit. A plurality ofcircuits may be used for the storage circuit, and SRAM, flash memory,ROM, FeRAM, or the like can be used. A storage circuit in which anorganic compound layer is used for a storage element portion may beused.

A signal sent from a interrogator 816 as an electric wave is convertedinto an alternating electric signal in the antenna 814. By the powersupply circuit 802, a power supply voltage is generated using thealternating electric signal and supplied to each circuit using a powersupply wiring. By the clock generation circuit 804, various kinds ofclock signals are generated based on the alternating signal inputtedfrom the antenna 814 and are supplied to the control circuit 810. By thedata demodulation circuit 806, the alternating electric signal isdemodulated and supplied to the control circuit 810. By the controlcircuit 810, various kinds of arithmetic processing is conducted inaccordance with the inputted signal. By the storage circuit 812, aprogram, data, and the like that are used by the control circuit 810 arestored. In addition, the storage circuit 812 can be used as an operationarea in arithmetic processing. Then, data is sent from the controlcircuit 810 to the data modulation circuit 808, whereby load modulationcan be added to the antenna 814 in accordance with the data from thedata modulation circuit 808. The interrogator 816 receives the loadmodulation added to the antenna 814 by an electric wave, and as aresult, the interrogator 816 can read data.

The RFID tag may have a structure in which an electric power is suppliedto each circuit by an electric wave without using power supply(battery), or a structure in which power supply (battery) is mounted,and electric power may be supplied to each circuit by an electric waveand power supply (battery).

By using the structure shown in this embodiment mode, an RFID tag thatcan be folded can be manufactured. Accordingly, an RFID tag can beattached to a curved surface portion of a wheeled vehicle.

It is to be noted that the above method for manufacturing an RFID tag isjust one example, and any RFID tags may be used as long as the functionof the present invention can be secured.

In this embodiment mode, calculation of speed, examination of speedingor not, or the like are collectively conducted by the server computer.However, the structure of the present invention is not limited thereto.One or a plurality of computers (connected to the server computer andpositioned at a lower part of the server computer) is assigned to anindividual interrogator or interrogators in the predetermined region,and each of the interrogators and the computers are connected, wherebyspeed of the wheeled vehicle in the given region can be calculated. Inthis case, flow up to examination of speeding or not can be conducted bythe computer at the lower part; therefore, the amount of informationprocessing of the server computer can be significantly reduced.

By using the wheeled vehicle and the speed measurement system shown inthis embodiment mode, crackdown on speeding can be easily conducted.That is, small-sized equipment as compared with the conventionalautomatic speed check equipment is used, and the equipment is easilyplaced in regions other than the specific region. Further, in the caseof using the system of this embodiment mode, it is not necessary tophotograph the drivers and the like, which is a different point from thecase of using the conventional automatic speed check equipment.Therefore, it is not necessary to post a sign of placement of theautomatic speed check equipment in advance. Thus, an effect of deterringdriving with speed exceeding legal speed is improved, and crackdown onspeeding becomes effective.

Furthermore, the speed measurement system shown in this embodiment modehas no imaging portion and is small-sized; therefore, maintenancethereof is easy and it is extremely effective for prevention ofmalfunction of the equipment.

In a case of comparing the system in this embodiment mode with a methodfor using ETC or VICS, there are advantages that power supply from thewheeled vehicle is unnecessary and that it is difficult for thepossessors of the wheeled vehicles to turn ON/OFF the RFID tag. That is,it is significantly effective in conducting crackdown on speeding or thelike. Since the unit price of the RFID tag is extremely cheap, if allwheeled vehicles are required to set the RFID tag by default, the chargeto the possessors of the wheeled vehicle is very small. Accordingly, itis preferable to use the speed measurement system shown in thisembodiment mode for crackdown on speeding or the like from the aspect offairness.

Embodiment Mode 2

In this embodiment mode, another example of a wheeled vehicle mountedwith an RFID tag and a speed measurement system using the RFID tag willbe described below with reference to FIGS. 9A and 9B and FIG. 10.

FIGS. 9A and 9B typically show a method for measuring speed of thisembodiment mode. In FIGS. 9A and 9B, an RFID tag 902 having a memoryportion in which unique vehicle ID is held is mounted on a wheeledvehicle 904. The wheeled vehicle 904 approaches a first interrogator 906placed on a road 900 or passes through the first interrogator 906 (seeFIG. 9A). At this time, the first interrogator 906 sends vehicle ID thatis obtained by communication with the RFID tag to a server computer 910that is network-connected. The server computer 910 holds the vehicle IDand information on date and time of the vehicle ID that is obtained bythe first interrogator 906, simultaneously.

At this time, a communication device 912 set on the wheeled vehiclesends information on date and time and speed information that isuniquely measured by the wheeled vehicle to the RFID tag 902, and theRFID tag 902 holds the information. Speed information that is uniquelymeasured by the wheeled vehicle indicates, for example, speedinformation that is extracted relative to the speedometer of the wheeledvehicle or the like.

Next, the wheeled vehicle 904 approaches a second interrogator 908 orpasses through the second interrogator 908 (see FIG. 9B). At this time,the server computer 910 holds the vehicle ID and information on date andtime of the vehicle ID that is obtained by the second interrogator 908,simultaneously, with the similar procedure in a case of passing throughthe first interrogator 906.

As similar to the case of passing through the first interrogator, thecommunication device 912 set on the wheeled vehicle sends information ondate and time and speed information that is uniquely measured by thewheeled vehicle to the RFID tag 902, and the RFID tag 902 holds theinformation.

After that, the server computer extracts a pair of information on dateand time with the same vehicle IDs, and a difference thereof iscalculated. That is, time period that is needed for the wheeled vehicle904 driven from a point A where the first interrogator 906 is placed toa point B where the second interrogator 908 is placed is calculated.

The distance between the point A and the point B is measured in advance,and the distance is divided by the calculated time period, wherebyaverage speed between the point A and the point B can be determined.

In a case where the average speed exceeds legal speed, the servercomputer holds data of date and time, place (including unique IDassigned to the interrogator), speed, excess of speed, and the like. Ata later date, in accordance with the data, a notification of speedingcan be sent to a possessor of the wheeled vehicle.

In a method for measuring speed in this embodiment mode, speedinformation that is uniformly measured by the wheeled vehicle can beheld in a memory portion in the RFID tag 902 separately from speedinformation that is measured by the system. Thus, if malfunction of thespeed measurement system occurs and examination of speeding isconducted, whether or not malfunction occurs can be verified.

In a method for measuring speed in this embodiment mode, thecommunication device set on the wheeled vehicle holds information ondate and time and speed information in the memory portion in the RFIDtag every time the wheeled vehicle and the interrogator communicateswith each other. However, it is not limited thereto. For example, onlywhen the wheeled vehicle communicates with the first interrogator oronly when the wheeled vehicle communicates with the second interrogator,the communication device set on the wheeled vehicle may hold informationdate and time and speed information in the memory portion in the RFIDtag. Alternatively, only when excess of speed is determined, informationon date and time and speed information may be held in the memory portionin the RFID tag.

In the structure in which information on date and time and speedinformation are held only when excess of speed is determined, the servercomputer instantaneously determines whether or not speed is exceededwhen the RFID tag communicates with the second interrogator. In a caseof excess of speed, the sever computer can send a signal of excess ofspeed to the RFID tag through the second interrogator. The RFID tag thatreceives the signal of excess of speed requests information on date andtime and speed information from the communication device set on thewheeled vehicle. In response, the communication device sends informationon date and time and speed information that is uniquely measured by thewheeled vehicle to the RFID tag.

Naturally, a third interrogator may be provided in addition to the firstinterrogator and the second interrogator. In this case, after speed ismeasured by the first interrogator and the second interrogator, andwhether or not that speed is exceeded is determined by the servercomputer, a signal that speed is exceeded is sent to the RFID tag by thethird interrogator.

It is to be noted that information held in the RFID tag is not limitedto only information on date and time and speed information. For example,information on a place where speed is exceeded and the like may be heldtogether.

Although communication of the RFID tag and the communication device isperformed by wired communication in this embodiment mode, thecommunication may be performed by wireless communication.

FIG. 10 shows a flow chart for calculating speed of the wheeled vehicleshown in the above description.

As a step S1000, the first interrogator detects vehicle ID of thewheeled vehicle that approaches or passes through the firstinterrogator. As a step S1002, the first interrogator stores the vehicleID and information on date and time on the server computer.

At the same time as communication with the first interrogator, as a stepS1004, the RFID tag requests information on date and time and speedinformation from the communication device. As a step S1006, the RFID tagholds information on date and time and speed information from thecommunication device in the memory portion.

As a step S1008, the second interrogator detects vehicle ID of thewheeled vehicle that approaches or passes through the secondinterrogator. As a step S1010, the second interrogator stores thevehicle ID and information on date and time on the server computer.

At a same time as communication with the second interrogator, as a stepS1012, the RFID tag requests information on date and time and speedinformation from the communication device. As a step S1014, the RFID tagholds information on date and time and speed information from thecommunication device in the memory portion.

After the step S1010, as a step S1016, the server computer extracts apair of information on date and time with the same vehicle IDs. It is tobe noted that the step S1016 may be conducted simultaneously with thestep S1010. In this case, the server computer extracts information onthe vehicle ID (information stored by the step S1002) that correspondsto the vehicle ID detected by the step S1008, and calculates speed inthe subsequent step.

Next, as a step S1018, the server computer calculates time period thatis needed for driving between the first interrogator and the secondinterrogator from the extracted information on date and time, andcalculates average speed using the distance between the firstinterrogator and the second interrogator.

By the subsequent step S1020, the calculated average speed and legalspeed are compared to examine speeding or not. Here, in a case wherespeeding is determined (a case of YES in FIG. 10), information onspeeding such as date and time, place (including unique ID assigned tothe interrogator or the like), speed, and excess of speed is stored onthe server computer as a step S1022. To the contrary, in a case of notspeeding, the flow is completed without storing information on speeding.

A setting portion of the RFID tag on the wheeled vehicle, a method forplacing the interrogators on the road, a method for manufacturing anRFID tag, and the like are similar to those of Embodiment Mode 1.Therefore, they are omitted here.

By using the wheeled vehicle and the speed measurement system shown inthis embodiment mode, crackdown on speeding becomes easy. That is, sincesmall-sized equipment in comparison with the conventional automaticspeed check equipment is used, the equipment in this embodiment mode iseasily placed in regions other than the specific region. Further, it isnot necessary to photograph the drivers and the like, which is adifferent point from the case of using the conventional automatic speedcheck equipment. Therefore, it is not necessary to post a sign ofplacement of the automatic speed check equipment in advance. Thus, aneffect of deterring driving with speed exceeding excessive legal speedis improved, and crackdown on speeding becomes effective.

Furthermore, the speed measurement system shown in this embodiment modehas no imaging portion and is small-sized; therefore, maintenancethereof is easy and it is extremely effective for prevention ofmalfunction of the equipment.

In a case of comparing the system in this embodiment mode with a methodfor using ETC or VICS, there are advantages that power supply from thewheeled vehicle is unnecessary and that it is difficult for thepossessors of the wheeled vehicles to turn ON/OFF the RFID tag. That is,it is significantly effective in conducting crackdown on speeding or thelike. Since the unit price of the RFID tag is extremely cheap, if allwheeled vehicles are required to set the RFID tag by default, the chargeto the possessors of the wheeled vehicle is very small. Accordingly, itis preferable to use the speed measurement system shown in thisembodiment mode for crackdown on speeding or the like from the aspect offairness.

Further, the wheeled vehicle shown in this embodiment mode is providedwith the communication device for exchanging information with the RFIDtag. Accordingly, since speed information that is uniquely measured bythe wheeled vehicle can be held in the memory portion in the RFID tag,if malfunction of the speed measurement system occurs, verification ofwhether or not malfunction occurs can be performed.

This embodiment mode can combined with Embodiment Mode 1 as appropriate.

Embodiment Mode 3

In this embodiment mode, an example of a wheeled vehicle mounted with anRFID tag and a vehicle information system using the wheeled vehicle willbe described below with reference to FIGS. 11A to 13B.

Although it is a main object of the speed measurement system of thepresent invention to measure speed, another useful system can beconstructed using the similar structure. For example, by using uniquevehicle ID for an RFID tag mounted on a wheeled vehicle, a system thatcan be used for finding a stolen vehicle can be constructed. Inaddition, a system by which tracking a desired wheeled vehicle can beeasily performed can be constructed.

FIGS. 11A to 11C schematically show a system that can be used forfinding a stolen vehicle or the like. In FIGS. 11A to 11C, an RFID tag1102 having a memory portion where unique vehicle ID is held is mountedon a wheeled vehicle 1104. The wheeled vehicle 1104 approaches a firstinterrogator 1106 placed on a road 1100 or passes through the firstinterrogator 1106 (see FIG. 11A). At this time, the first interrogator1106 sends vehicle ID that is obtained by communication with the RFIDtag to a server computer 1110 that is network-connected. The servercomputer 1110 examines whether or not the vehicle ID is vehicle ID of astolen vehicle. In a case where it is vehicle ID of the stolen vehicle,the server computer 1110 stores information on date and time of thestolen vehicle passing through the first interrogator 1106.

Next, the wheeled vehicle 1104 approaches a second interrogator 1108 orpasses through the second interrogator 1108 (see FIG. 11B). At thistime, the server computer 1100 obtain vehicle ID with the similarprocedure in the case of passing though the first interrogator 1106. Inthe case where the vehicle ID is vehicle ID of the stolen vehicle, theserver computer also stores information on date and time of the stolenvehicle passing.

Thus, the direction of the driven stolen vehicle can be examined. Byproviding the interrogator of the present invention on a major road, itbecomes possible to specify a region where the stolen vehicle ispresent.

After the region where the stolen vehicle is present is almostrestricted by the above system, the stolen vehicle is searched using theinterrogator exchanging information with the RFID tag set on the wheeledvehicle, whereby effort and cost spent for search and the like can bedrastically reduced. Since the interrogator for exchanging informationwith the RFID tag set on the wheeled vehicle is small-sized equipment,the interrogator can be carried by police officers and the like inpatrol. Accordingly, it is effective for find the stolen vehicle and thelike. For example, in FIG. 11C, when an RFID tag 1114 is mounted on astolen vehicle 1112, whether or not the wheeled vehicle is the stolenvehicle can be easily examined by a portable interrogator 1116.

The structures shown in FIGS. 11A and 11B are basically similar to thestructure of the speed measurement system described in EmbodimentMode 1. That is, at the same time of examination of whether or not thewheeled vehicle is the stolen vehicle, speed may also be measured. It isto be noted that, in a system that is used for finding the stolenvehicle, an RFID tag having a memory portion in which information on thestolen vehicle can be written is mounted on the wheeled vehicle, wherebyinformation on the stolen vehicle may be written in the RFID tag whenpassing through the first interrogator or the second interrogator.

FIG. 12 shows a flow chart for examining whether or not the wheeledvehicle is the stolen vehicle shown in the above description.

As a step S1200, the first interrogator detects vehicle ID of thewheeled vehicle that approaches or passes through the firstinterrogator. As a step S1202, the first interrogator examines whetheror not the detected vehicle ID is that of the stolen vehicle. In a casewhere the detected vehicle ID is that of the stolen vehicle, the servercomputer stores the vehicle ID and information on date and time as astep S1204. In a case where the detected vehicle ID is not that of thestolen vehicle, the server computer does not store the vehicle ID andthe information on date and time, and the flow proceeds to next step.

Next, as a step S1206, the second interrogator detects vehicle ID of thewheeled vehicle that approaches or passes through the secondinterrogator. As a step S1208, the second interrogator examines whetheror not the detected vehicle ID is that of the stolen vehicle. In a casewhere the detected vehicle ID is that of the stolen vehicle, the servercomputer stores the vehicle ID and information on date and time as astep S1210. In a case where the detected vehicle ID is not that of thestolen vehicle, the server computer does not store the vehicle ID andinformation on date and time, and the flow is completed.

After that, as a step S1212, by comparing a pair of information on dateand time with the same detected vehicle IDs by the first interrogatorand the second interrogator, calculation of the direction of the drivenstolen vehicle is performed. When a interrogator that can be used forthis system is provided on a major road, the region where the wheeledvehicle is present can almost be examined; therefore, the present regionof the wheeled vehicle is calculated as a step S1214.

When the vehicle ID detected by the step S1202 is not that of the stolenvehicle, FIG. 12 shows that the flow proceeds to next step. However, theflow may be completed by the step S1202.

In FIGS. 13A and 13B, an example in which interrogators are placed on amajor road is shown. In FIGS. 13A and 13B, “x” marks indicate theplacement of the interrogators. When the interrogators are placed as inFIG. 13A, whether or not the stolen vehicle is present in a regionindicated by the broken line in the drawing can be examined.

In FIG. 13B, another example of placement of interrogators is shown. Asshown in FIG. 13B, by providing the interrogators on a major road, theregion where the stolen vehicle is present can be examined. Although thecase in which the roads are set out neatly in a grid for convenience isshown in FIGS. 13A and 13B, it is not limited thereto. The partition ofthe regions is not limited to the examples shown in FIGS. 13A and 13B.

A setting portion of the RFID tag on the wheeled vehicle, a method forplacing the interrogators on the road, a method for manufacturing anRFID tag, and the like are similar to those of Embodiment Mode 1.Therefore, they are omitted here.

By using the system shown in this embodiment mode, the stolen vehiclecan be easily found. The system shown in this embodiment mode has noimaging portion and is small-sized; therefore, maintenance thereof iseasy and it is extremely effective for prevention of malfunction of theequipment.

Further, a car-mount device that needs power supply from the wheeledvehicle is unnecessary, and it is extremely difficult for the possessorsof the wheeled vehicles to turn ON/OFF the RFID tag. That is, it issignificantly advantageous to track the desired wheeled vehicle infinding the stolen vehicle. Since the unit price of the RFID tag isextremely cheap, if all wheeled vehicles are required to set the RFIDtag by default, the charge to the possessors of the wheeled vehicle isvery small. Accordingly, it is preferable to use the speed measurementsystem shown in this embodiment mode from the aspect of fairness.

The interrogator for exchanging information with the RFID tag set on thewheeled vehicle, which is used in this system, is small-sized equipment,and it can be carried by police officers and the like in patrol.Therefore, the stolen vehicle can be easily found by using this system.In addition, the desired wheeled vehicle can be easily tracked.

This embodiment mode can be combined with Embodiment Mode 1 or 2 asappropriate.

Embodiment Mode 4

In the system of the present invention, it is necessary to send andreceive a signal between an RFID tag and a interrogator in a short timeof a wheeled vehicle passing. Therefore, in order to improve responsespeed of the RFID tag, it is preferable to have a power supply in theRFID tag itself. In this embodiment mode, a structure of the RFID tag,which have a battery capable of being charged by wireless communication,and the interrogator will be described with reference to FIGS. 14A to15B.

As shown in FIG. 14A, an RFID tag described in this embodiment mode hasan antenna (or an antenna and a capacitor (also referred to as aresonant capacitor)) 1402, a rectifier circuit 1404, a voltage controlcircuit (also referred to as a regulator) 1406, a battery 1408, a chargecontrol circuit 1410, and a processing circuit 1412 for performinginformation processing of the wire communication or the like. An outputof the antenna 1402 is connected to an input of the rectifier circuit1404, and an output of the rectifier circuit is connected to an input ofthe voltage control circuit 1406. An output of the voltage controlcircuit 1406 is connected to an input of the battery 1408 through aswitch A 1414. The charge control circuit 1410 is connected to thebattery 1408 to monitor a charge condition of the battery 1408, and inresponse to the condition, the charge control circuit 1410 controlsON/OFF of the switch A 1414.

Here, a structure in which a diode is used as the switch A 1414 and thecharge control circuit 1410 is omitted may be employed. The voltagecontrol circuit 1406 may be a control circuit of a voltage and acurrent.

Next, an example of a structure of the processing circuit 1412 is shownin FIG. 14B. The processing circuit 1412 may have a structure thatincludes a regulator 1422 connected to the battery 1408 through a switchB 1420, a demodulation circuit 1424 and a modulation circuit 1426connected to the antenna 1402, and a logic circuit 1428. The logiccircuit 1428 includes a plurality of circuits having functions ofdemodulation, arithmetic, storage, and the like.

The battery 1408 is connected to the processing circuit 1412 through theswitch B 1420. The switch B 1420 is controlled depending on a chargecondition of the battery 1408 similarly to that of the switch A 1414.For example, when the voltage of the battery 1408 becomes a value of V₁or more, the switch B 1420 is turned On. When the voltage of the battery1408 becomes a value V₂ (V₁>V₂) or less by consuming the power of thebattery, the switch B 1420 is turned OFF. The V₁ may be a voltage enoughto drive the processing circuit 1412 connected to the battery 1408 orthe like, and V₂ may be a minimum voltage needed for driving.

Next, an example of a interrogator that can communicate with the RFIDtag and charge the battery is shown in FIG. 14C. The interrogatorincludes a control system 1430 and an antenna (or an antenna and acapacitor) 1432.

As the simplest example in which the battery of the RFID tag is chargedfrom the interrogator, communication is performed using anelectromagnetic wave with equivalent amplitudes as shown in FIG. 15A. Amethod for charge at this time is shown in a flow chart of FIG. 15B.

First, as a step S1502, an electromagnetic wave with equivalentamplitudes starts to be sent from an antenna of a charger. When the RFIDtag receives the electromagnetic wave as a step S1504, the switch Aturns ON as a step S1506, and the charge to battery starts. At thistime, the charge control circuit monitors a charge condition to thebattery as a step S1508. When a voltage of the battery becomes apredetermined value (given value) or more (YES), the RFID tag sends asignal of completion of the charge as a step S1510. The interrogatorreceives the signal as a step S1512, and the electromagnetic wave stopsto be sent as a step S1514. When the voltage of the battery does notreach a predetermined value (NO), the flow returns to the step S1506,and the charge is continuously performed.

By using the RFID tag and the interrogator shown in this embodimentmode, a signal in the system of the present invention can be sent andreceived more accurately and quickly. Thus, probability of malfunctionof the system can be further reduced.

The interrogator shown in this embodiment mode is small-sized equipmentas compared with the conventional automatic speed check equipment, andit is easy to place in regions other than the specific region. Further,the interrogator has no imaging portion and is small-sized; therefore,maintenance thereof is easy and it is extremely effective for preventionof malfunction of the equipment.

This embodiment mode can be combined with Embodiment Modes 1 to 3 asappropriate.

Embodiment Mode 5

In this embodiment mode, another example of a wheeled vehicle mountedwith an RFID tag and an information system using the wheeled vehiclewill be described.

Although it is a main object of a speed measurement system of thepresent invention to measure speed, another useful system can beconstructed using a similar structure. For example, by holdinginformation such as accident histories and restoration histories of thewheeled vehicle in an RFID tag, histories such as accident histories andrestoration histories of the wheeled vehicle, which is difficult to bediscriminated, can be easily obtained.

As another example, an example in which information such as tax paymentand penalty payment is held in an RFID can be given. Accordingly, itbecomes easy to collect tax and penalty in a case where the tax and thepenalty are not paid. Further, by placing interrogators as appropriatein a parking area, information on placement of wheeled vehicles can beeasily checked. Further, by holding information on date and time of thewheeled vehicles in the parking area coupled with turning ON/OFF of anengine thereof, whether or not the wheeled vehicles are derelictvehicles of illegally parked (parking duration) can be easily bedetermined. Furthermore, by providing the RFID tag for the wheeledvehicle, management capability of the wheeled vehicles by manufacturersand the like is improved.

The interrogator that can be used in this embodiment mode is small-sizedequipment, and it can be placed in various places without selectingsetting positions. In addition, the interrogator is easily carriedbecause the size thereof is small. Further, it becomes a big advantageof the RFID tag that supply of power from the wheeled vehicle isunnecessary as compared with the existing equipment such as ETC andVICS. Therefore, various systems can be constructed as shown in thisembodiment mode.

This embodiment mode can be combined with Embodiment Modes 1 to 4 asappropriate.

Embodiment Mode 6

In this embodiment mode, an example of using a wheeled vehicle mountedwith an RFID tag, an information system of the wheeled vehicle, and theexisting automatic speed check equipment will be described.

By using the system of the present invention combined with the existingautomatic speed check equipment, the system of the present invention canbe supplemented. For example, identification information on a wheeledvehicle can be detected by the system of the present invention, and theregistration number (car registration plate) of a wheeled vehicle can bedetected by the existing automatic speed check equipment. Accordingly,even when identification information on a wheeled vehicle that is heldin the RFID tag and the registration number of a wheeled vehicle do notcorrespond to each other, in other words, the car registration number isaltered in the stolen vehicle, the wheeled vehicle can be easily found.Also, if the system of the present invention does not function becauseof breakdown of the RFID tag, the wheeled vehicle of an RFID tag whichdoes not function can be distinguished using the existing automaticspeed check equipment. Similarly, it is possible to set an RFID tagthoroughly by distinguishing the wheeled vehicles on which an RFID tagis not set.

It is to be noted that various combinations of the system of the presentinvention and the existing automatic speed check equipment are employed,and the combination is not particularly limited. For example, the systemof the present invention can be placed in the same region where theexisting automatic speed check equipment is placed.

This embodiment mode can be combined with Embodiment Modes 1 to 5 asappropriate.

The present invention can have various structures other than thestructure shown in the embodiment modes in accordance with the purpose.Therefore, the usage of the wheeled vehicle and the system shown in thepresent invention is not limited to description of this specification.

This application is based on Japanese Patent Application serial no.2006-257822 filed in Japan Patent Office on Sep. 22, 2006, the entirecontents of which are hereby incorporated by reference.

1. A wheeled vehicle comprising: an RFID tag comprising a memoryportion, a battery configured to be charged, and a charge controlcircuit, wherein the memory portion is configured to hold identificationinformation on the wheeled vehicle, wherein the RFID tag is configuredto send the identification information to an interrogator in a case ofreceiving a signal from the interrogator, and wherein, in the case ofreceiving the signal from the interrogator, the charge control circuitis configured to examine whether or not a voltage of the battery reachesa given value, and to charge the battery in a case the voltage of thebattery does not reach the given value.
 2. The wheeled vehicle accordingto claim 1, further comprising: a communication device set on thewheeled vehicle, wherein the communication device is configured to sendspeed information that is measured by the wheeled vehicle to theinterrogator, in a case where the RFID tag communicates with theinterrogator, and wherein the memory portion is configured to hold thespeed information that is measured by the wheeled vehicle.
 3. Thewheeled vehicle according to claim 1, wherein the RFID tag comprises athin film integrated circuit sealed with a first base and a second base,and wherein each of the first base and the second base is an antistaticfilm.
 4. The wheeled vehicle according to claim 1, wherein the RFID tagis attached to or embedded in any of a mirror portion, a light portion,or a window portion of the wheeled vehicle.
 5. The wheeled vehicleaccording to claim 1, wherein the identification information includesany of speed information, information on date and time, information ontheft, information on accident history, information on restorationhistory, information on tax payment, and information on penalty payment.6. An RFID tag comprising: a memory portion; a battery configured to becharged; and a charge control circuit, wherein the memory portion isconfigured to hold identification information on a wheeled vehicle,wherein the RFID tag is configured to send the identificationinformation to an interrogator in a case of receiving a signal from theinterrogator, and wherein, in the case of receiving the signal from theinterrogator, the charge control circuit is configured to examinewhether or not a voltage of the battery reaches a given value, and tocharge the battery in a case the voltage of the battery does not reachthe given value.
 7. The RFID tag according to claim 6, furthercomprising: a thin film integrated circuit sealed with a first base anda second base, and wherein each of the first base and the second base isan antistatic film.
 8. The RFID tag according to claim 6, wherein theidentification information includes any of speed information,information on date and time, information on theft, information onaccident history, information on restoration history, information on taxpayment, and information on penalty payment.
 9. A speed measurementsystem comprising: a first interrogator configured to detect firstidentification information on an RFID tag set on a wheeled vehicle; asecond interrogator configured to detect second identificationinformation on the RFID tag set on the wheeled vehicle; a computer thatis connected to the first interrogator and the second interrogator,wherein the second interrogator is placed to have a given distance fromthe first interrogator, wherein the second interrogator is configured todetect the second identification information, after the firstinterrogator detects first identification information, wherein thecomputer is configured to hold first timing information on date and timein detecting the first identification information, wherein the computeris configured to hold second timing information on date and time indetecting the second identification information, wherein the computer isconfigured to calculate average speed of the wheeled vehicle between thefirst interrogator and the second interrogator, by the first timinginformation, the second timing information and the given distance,wherein the RFID tag comprises a memory portion, a charge controlcircuit and a battery configured to be charged, and wherein, when theRFID tag receives a signal from at least one of the first interrogatorand the second interrogator, the charge control circuit is configured toexamine whether or not a voltage of the battery reaches a given valueand to charge the battery in a case the voltage of the battery does notreach the given value.
 10. The speed measurement system according toclaim 9, wherein the computer is a server computer or a computerconnected to a lower part of the server computer.
 11. The speedmeasurement system according to claim 9, wherein the wheeled vehiclecomprises a communication device, wherein the communication device isconfigured to send speed information that is measured by the wheeledvehicle to at least one of the first interrogator and the secondinterrogator, in a case where the RFID tag communicates with theinterrogator, and wherein the memory portion is configured to hold thespeed information that is measured by the wheeled vehicle.
 12. The speedmeasurement system according to claim 9, wherein the RFID tag comprisesa thin film integrated circuit sealed with a first base and a secondbase, and wherein each of the first base and the second base is anantistatic film.
 13. The speed measurement system according to claim 9,wherein the RFID tag is configured to hold any of identificationinformation on a wheeled vehicle, speed information, information on dateand time, information on theft, information on accident history,information on restoration history, information on tax payment, andinformation on penalty payment.